Display screen or portion thereof with transitional graphical user interface



FIG. 1 is the first image in a sequence of a display screen or portion thereof with transitional graphical user interface showing our new design;

FIG. 2 is the second image thereof;

FIG. 3 is a partial enlarged view of FIG. 1 , showing only the upper half of the image to clearly show the claimed subject matter; and,

FIG. 4 is a partial enlarged view of FIG. 2 , showing only the upper half of the image to clearly show the claimed subject matter.

In FIGS. 1-2 , the outermost dashed broken line rectangle illustrates a display screen. In FIGS. 3-4 , the vertical lines at the left and right sides of each figure and the horizontal line at the top of each figure illustrate a portion of a display screen. In all figures, the remaining dashed broken lines illustrate portions of the graphical user interface. None of the broken lines form part of the claimed design.

The appearance of the graphical user interface sequentially transitions between the images shown in FIGS. 1-2 . This process or period in which one image transitions to another image forms no part of the claimed design. 

CLAIM The ornamental design for a display screen or portion thereof with transitional graphical user interface, as shown and described. 